At the third assessment (week 4), a follow up physical and neurological examination will be done, including vital signs, and the mental testing, including the tests of cognition, function and behavior will be repeated. An assessment will be made to determine whether adverse events occurred. Adverse events will be assessed by review of the subject's seizure log, physician observation, direct questioning and spontaneous reports. The date, number, duration and type of seizures any subject experiences will also be documented. In cases where levetiracetam is an add-on agent, we will attempt to taper the preceding medications if seizure control has been demonstrated. Cognitive testing will be done when subjects are not in a post-ictal state. Any subject who has had a seizure with generalization within 24 hours of their scheduled testing will be rescheduled to another day within one week.